Reaction #2358485

Reaction equation

2-fluoro-5-(trifluoromethyl)benzaldehyde

methyl thioglycolate

potassium carbonate

DMF

→

methyl 5-(trifluoromethyl)benzo[b]thiophene-2-carboxylate

Yield 93.0%

Solvents

water

Conditions

Workup

1. 1
   Temperaturethe reaction mixture was cooled to room temperature
2. 2
   Extractionextracted with tert-butyl methyl ether 3 times
3. 3
   WashThe combined organic layer was washed with water
4. 4
   DryingThe mixture was dried over magnesium sulfate
5. 5
   Concentrationconcentrated under reduced pressure
6. 6
   OtherThe residue was recrystallized from methanol

Procedure

A mixture of 5.0 g of 2-fluoro-5-(trifluoromethyl)benzaldehyde, 3.3 g of methyl thioglycolate, 4.0 g of potassium carbonate and 50 ml of DMF was stirred at 60° C. for 2 hours, and then the reaction mixture was cooled to room temperature. To the reaction mixture was added water, and extracted with tert-butyl methyl ether 3 times. The combined organic layer was washed with water, followed by saturated aqueous sodium chloride solution. The mixture was dried over magnesium sulfate, and then concentrated under reduced pressure. The residue was recrystallized from methanol to obtain 6.3 g of methyl 5-(trifluoromethyl)benzo[b]thiophene-2-carboxylate (the present compound 1).

Source